alone and a cyclo(Lys-Gly) DKP carrier bearing as peptide model, the tau protein hexapeptide VQIVYK sequence. The different carrier systems were synthesized and radiolabeled using one of the free domains. The stability, biodistribution, and ability to cross blood-brain barrier were investigated in vivo in mice for 99m Tc-DKP scaffolds, 99m Tc-HVQIVYK peptide alone, and 99m Tc-DKP-VQIVYK. 125 I-labelled